Roll for rolling mills



F. M. CANDA.

ROLL FUR ROLLING MILLS.

PLlcATmN FILED Dac. n. :92o

PtentedSept. 5, 1922.

, differ/yay Patented Sept. 5, 1922.

' cmu* FERDINAND MORA CANDA, or NRW YORK, N. Y. n

y ROLL FOR RoLLINGjr/rrLLs,

Application yfiled December 17, I17929. Serial` No; .i

ed 'for use Iin ball rolling machines, inay'also serve other purposes.

In the operation of ',rqllinggmills 1t 1s im,-

portant to maintain Vthe peatinfglvfaces or` surfaces of the rollsaccurateand true and the necessity for frequentg-trueingx of the rolls'adds considerablyy to the expense of maintenance. In the type of rollshaving ridges to shape the material, wear of these Accord` ridges isparticularly undesirable. ingly, I construct those portions ofthe roll,which are mainly subject to wear, of very hard steel. It frequentlyhappens that one or more of the ridges become worn 'or de'- fectivewhile the remainder of the roll is perfect. I have, therefore, devised aroll in which each ridge portion is separately formed and may be removedor replaced and by so doing the life of the roll is very greatlylengthened. Moreover this change of parts can be effected yquickly sothat the loss of time heretofore necessitated by trueing of the rolls isgreatly reduced and the expense of replacing a worn or partiallydefective roll with an entire new one is obviated.

The object of my invention, therefore, isv

to reduce the wear of rigid rolls and thus to prolong their life, and toprovide for the ready replacement of only those portions of the roll`which become worn or defective.

In the accompanying drawings, Figure 1 is a longitudinal sectional viewof ya mill roll embodying my invention, the section being taken on theline 1-1 of Fig. 3; Fig. 2 isa longitudinal sectional View on the line 22 of Fig. 4t, showing another form of my invention; Figs. 3 and 4c aretransverse sectional views on the lines 3-3 of Fig. 1 and 1:4 of Fig. 2,respectively.

I construct the roll of a series of rings i or disks which are boltedtogether and secured in any suitable manner upon the roll shaft. In theform shown in Fig. 1 the sharp ridges of the roll are formed on theperipheries of narrow disks 5' of a very gradewofssteel, toolsteelandwhich may be'oneof the steels known inthe tradey 1 as fhigh f speed toollsteelQ. The troughs of the grooves `are vformed upon wider disks-6interposed between Ithe disks 5 andformedcf atougherwmetal, preferablyunliardened A'forged,'steel. All of the disks` are 'provided withperforations Lto receive thevbolt's I 8. after they have been-'assembledon/thefshaft whichy is of mildsteel andto what they are ticked by @key12; y

Underisome conditions `I found that mayffdispense, withtheforged'steelvdisks 6 f and form thejrollsfentirely yfrom disks of disk withoppositely disposed",curves symmetrically arranged to form central.ridges, each groove being formed' by *the4 curves of adjacent disks. Ihave illustrated this u specially,hardgrade.steel, constructingtheconstruction in Fig. 2 wherein the entire roll is formed of a very hardgrade ofsteel disks 5a, each disk being the width of one of the grooves.The disks are assembled on the shaft and bolted together in they mannerdescribed in connection with the form shown in Fig. 1.

I have illustrated rolls which are suitable for use in ball rollingmills such as shown in my applications for Letters Patent, Ser. No.329,774, iiled Oct. 10, 1919, Ser. No. 332,284, filed Oct. 2l, 1919, andSer. No. 334,030, filedO'ct. 28, 1919. It will be evident that'my methodof constructing rolls may be applied to other types, as for instance,such rolls having V-shaped grooves which arevused for rolling anglebars, particularly `the yso-called square root7 angle bar.

As previously stated, the rolls are especially intended to be used inmachines' for forming steel or other iron balls adapted for use inCrusher mills and the like. The blanks supplied to the machine areusually in the form' of rods, these blanks being preferably heated to asuitable forging or rolling temperature before they pass through themachine. Then the bar is pressed against the rolls, the sharp projectingribs or ridges cutinto the bar forming grooves which-divide it intosections, each corre-k sponding to one of the grooves of the rolls.r

As the operation proceeds, the ribs cut more deeplyV into the `bar andthe metal atthe shoulders of they sections into which the said bar isdivided is pressed inward toward the equatorial portions `of the formingballs. It is evident that the greatest strain and wear in this operationfalls upon the outer peripheral ribs or ridges of the rolls .which arerequired to continually cut or groove the blank bar. I have found thatthese ribs Will maintain their integrity and accurate shape for aconsiderable length of time if they are formed of a very hard steel suchas the high speed alloy steels and provided they are lso disposed thatthe strains will be symmetrical and uniformly distributed at the base ofthe ribs in the supporting metal. I accomplished this, purpose byforming the ribs symmetrically upon a central plane of the disk. Whenthe .disks have been rigidly bolted together upon the shaft theymutually brace 'each other against lateral thrusts, and forni, ineffect, VasolidV roll. At the same time any disk which becomes defectivefrom Wear, chipping yor breakage may be readily removed and replacedWith a new disk, therey by greatly prolonging the normal glife of thelentire roll, very materially reducing the expense `of maintenance asWell as sav' which merge into the curved faces of ad Y jacent disks oftougher metal.

2. rolling mill roll, comprising a grooved roll body formed ofjuxtaposed symmetrically shaped disks, certain of said disks beingcomposed of a hard grade of steel and provided with centrally disposedperipheral ribs whose opposite sides conform to the curvature of thegrooves ofthe roll body, each groove lextending over a plu-` r'ality ofdisks.

In testimony whereof, I have signed m name to this specification, thisy16th- 'day of December, 1920.

` FERDINAND MORA CANDA.

